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sergiotapia

I thought type-c was supposed to be the end-all compatibility design. You buy any type-c and it works to spec.

What gives?

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What gives is that this was not actually a type C cable, but an evil, broken cable mislabeled as a USB-C cable.

Right... but two questions stick their head up and want answers:

First, USB outlets are supposed to have a bit of a fuse. Why was this upfuckage so spectacular?

Second, why do USB type C ports/cables have 24 pins if there are only 4 wires? I can understand having a couple of extra ones for type/orientation detection and a doubling to support reversion, but 24 is a lot.

well, usb type C is supposed to have at least 9 wires, if I recall correctly. This is not a valid type C cable, but it was being sold as one, which is part of the outrage. (aside from the "killing devices" bit)

A "USB Type-C to USB 2.0 Type-A cable" has 4 wires (same as any USB 2.0 cable, really; only the plug in one end is different).

The problem is that this was being sold as a "USB Type-C to USB 3.1 Type-A cable", which is supposed to have 10 wires.

(A full USB Type-C cable has some 18 wires, since it wires both sides separately so the alternate modes which use both sides separately can work.)

> Why was this upfuckage so spectacular?

Because it had power wired to ground. This would be incredibly absurd in ANY variety of powered cable.

This is not merely "noncompliant with spec", it's "actively dangerous because it could start a fire and kill somebody".

I see. Of course it would be very difficult to defend against that. Thanks.

I don't know exactly why these ports aren't protected, but as for your second question, why assume there are only four wires, given there are a lot more pins? Wikipedia has a full pinout and wiring list and you can see there's a lot more going on than that:

https://en.wikipedia.org/wiki/USB_Type-C#Connector_pinouts_a...

USB-C is not merely a new connector for the old USB 2.0, but includes a lot more. It is backwards compatible, but goes well beyond that.

Why assume that, indeed. The salesman who sold me my lovely new macbook told me (when I said something skeptical about quick charging via a thin cable).

Feel free to vote me down for believing something a salesman said.

That'll learn ya.

(For the record, I didn't downvote.)

I'm not sure any spec for a power cable protects against switching V+ with ground.

The issue here is that some of the type-c cables Amazon is selling are not to spec, they are miswired. The warning here it to stick to reputable type-c manufacturers because miswired cables can damage devices.

The spec is fine but they mis-wired the cable in the factory, badly.

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